Research has already shown that guys do worse on cognitive tests when they're forced to interact with a lady beforehand. Now a new study reveals that all you need to render guys brainless is a woman's name on an instant message screen.

According to Miller-McCune, one of the same researchers who published the 2009 study finding that dudes get all stoopid when a lady is present has now found that she doesn't even have to be present. First, psychologist Johan Karremans, lead study author Sanne Nauts, and their team gave a group of 71 men and women a common cognitive test (the Stroop test, if you're curious). Then the subjects had to do another task with help — via instant message only — from a "monitor" with either a male or a female name. Then they took the Stroop test again. The dudes did way worse after an e-encounter with a lady monitor, but dude monitors didn't affect their performance. And women weren't affected either way. In a second experiment, participants were told that a man or a woman would IM them, but they never actually got any IMs — even this was enough to make guys screw up on the Stroop.

The study authors write, "together, these results suggest that an actual interaction is not a necessary prerequisite for the cognitive impairment effect to occur. Moreover, these effects occur even if men do not get information about the woman's attractiveness." The study can't explain why this happens, but Nauts et al theorize that maybe dudes are more likely than women "to perceive relatively neutral situations in sexualized terms" — and maybe all the mental energy they expend having sexy thoughts takes its toll on other brain functions.

Of course, plenty of ladies think about sex a lot too, but the way they act around potential partners may be different. Guys are socialized to think they have to be witty and funny to attract women, whereas women are told we need to look hot. The latter would, you'd think, take a cognitive toll too — but apparently not in this study. The research has a couple of obvious limitations — it appears to have focused on straight people, and, as Miller-McCune points out, on the very young (average subject age: 21). Hopefully as people get older they're a little more able to think with their heads and their dicks at the same time.